Difference In Diameter Between an 8 Inch Wheel with Tire and a 15 Inch Wheel with Tire

Published 12/15/2015

Products Featured in This Question

Kenda 4.80/4.00-8 Bias Trailer Tire with 8" White Wheel - 4 on 4 - Load Range C

(7908)

$54.23

Kenda Karrier ST205/75R15 Trailer Tire with Black Mod Wheel - 5 on 4-1/2

(2968)

$176.55

Question:

taking that same theory into consideration of 12 inch tires to 15 giving only 1.5 inch , would a 8 inch tire vs 15 then give you a 3.5 inch ?

asked by: Konrad

Expert Reply:

The height difference between an 8 inch wheel with tire and a 15 inch wheel with tire will really depend on the tire size on the wheel. It is true that an 8 inch wheel is 3-1/2 inches smaller in diameter than a 15 inch wheel, but with tires on the wheels the difference will likely be greater than 3-1/2 inches.

For example, the Kenda 4.80/4.00-8 Bias Trailer Tire with 8 Inch Wheel # AM30040 when inflated has a diameter of 16.1 inches, while the Kenda ST205/75-15 Radial Trailer Tire with 15 Inch Wheel # AM32238B when inflated has a diameter of 27-5/16 inches. The difference in these two tire and wheels is 5-1/2 inches, not 3-1/2 inches.

There are many other factors to consider when thinking about going from a 15 inch tire to an 8 inch tire. The weight capacity of an 8 inch tire can be much smaller than the capacity of a 15 inch tire.

Additionally, an 8 inch wheel will not fit over the hub and drum that accommodates a 15 inch tire. You would need a hub designed to fit an 8 inch wheel, and all but one of the hubs we carry for 8 inch wheels are idler hubs.

I have attached a help article that outlines diameters and load ranges of different size trailer tires for you.

expert reply by: Victoria B